Additive manufacturing or additive layer manufacturing is increasingly used for rapidly manufacturing prototype or even final components and is then also referred to as rapid prototyping and rapid manufacturing, respectively. In contrast to conventional manufacturing methods involving removal of material from a block of material by, e.g., cutting, drilling or other machining processes, additive manufacturing directly constructs a desired three-dimensional object layer by layer from a digital representation of the object. It is also known as 3D printing.
One type of additive manufacturing comprises dispensing or extruding material from which the product is to be manufactured from a nozzle of a dispensing head in order to provide a thin layer of the material on a support plate, and subsequently curing or hardening the dispensed material. The material may be dispensed or extruded e.g. in the form of small beads, and hardening of the dispensed material may be effected automatically by a suitable choice of the temperature and of the material. The material is applied to the support plate only in those portions corresponding to the product being manufactured. Subsequently, a further thin layer of the material is provided in the same manner on top of the initial layer in those portions corresponding to the product being manufactured. The process is repeated until the complete object is obtained. The material, which may be a thermoplastic or metal material, may be provided to the dispensing head in the form of a wire which may be unreeled from a coil. Corresponding 3D printing machines are also referred to as 3D printing machines using wire feed technology. The dispensing head is typically adapted to heat the material inside the dispensing head above its melting temperature or a glass transition temperature, and the dispensing head is mounted to be selectively movable linearly in horizontal and vertical directions under the control of a suitable control unit in order to enable the formation of the layers.
Particular additive manufacturing methods of this type are also referred to as fused deposition modeling (FDM).
As noted above, the object is directly built up layer by layer in a three-dimensional manner. This makes it possible to efficiently and rapidly manufacture different highly complex objects from various materials, in particular plastic materials and metal materials, using one and the same apparatus. For example, highly complex grid or honeycomb structures which are difficult to produce using other techniques can be easily manufactured. As compared to traditional methods, the complexity of the object has only little influence on the manufacturing costs.
Due to these advantages additive manufacturing methods of the above type find increasing application in various fields of technology, such as aircraft and automotive engineering. Amongst others, components, such as mounting brackets, are manufactured by additive manufacturing which must be later secured to other components, such as cables or ducts. It has turned out to be generally difficult or impossible to directly manufacture components by additive manufacturing on other components such that they are secured to each other. Thus, when manufacturing, for example, a mounting bracket it is necessary to secure the mounting bracket to the component to be mounted by the mounted bracket in a separate process step.